Abstract: This invention discloses a direct drive spindle assembly including a main fork formed by a base and a parallel pair of spaced fork arms and rotated about a first rotational axis. Moreover, the direct drive spindle assembly includes a first drive established by a hollow housing, a first motor stator and a first motor rotor, wherein the first motor rotor coupled with the base of the main fork drives the main fork to rotate about the first rotational axis. Furthermore, the direct drive spindle assembly includes a second drive contained in a room between the fork arms of the main fork and established by a second motor stator concentric with a second rotational axis, a second motor rotor and a rotor transmission ring, wherein the second rotational axis is perpendicular to the first rotational axis and the second motor stator is coupled with the fork arms of the main fork. In addition, the direct drive spindle assembly includes a spindle box having an orthogonal cross structure.